Pneumococci attach to type II lung cells during pneumonia. Previous studies have shown that transparent morphology on an agar plate is associated with the ability of pneumococci to attach to lung cells and infect mice. Opaque colonies can not. Surface appendages on the cocci which mediate attachment have not been described. We are investigating whether the increased sample size achieved with thick sections on the HVEM will improve our chances of finding low frequency surface differences between the two types of pneumococci. This will be the first visualization of an adhesive appendage for a gram positive bacteria.